
Asst. Prof @CarnegieMellon, @amazon Scholar, Prev: Visiting Researcher @Meta, Postdoc @Stanford, Ph.D. @RiceUniversity, Large-Scale ML, a fan of Dota2.
Joined November 2011
- Tweets621
- Following415
- Followers17K
- Likes1.5K
As data centers hit power limits, AI model needs an energy-efficient scaling axis. โก
Embedding scaling grows model capacity with minimal additional serving energy. STAPLE brings this to pretrained LLMsโwithout restarting pretraining from scratch.
๐ง How can we keep scaling LLMs with minimal changes in their serving energy?
DeepSeekโs Engram and our concurrent work STEM showed the promise of static sparse memory: large embedding tables with efficient access. But can mature pretrained models learn to use a newly added memory within a limited training budget, avoiding costly pretraining from scratch?
๐ Introducing STAPLE: a recipe to extend pretrained models' abilities with static sparse memory. Serving energy per token stays close to dense and >50% below MoE upcycling in high-throughput regime.
Scalable capacity, interpretable memory, and compatibility with MoE upcycling - without any meaningful increase in serving cost. ๐งต
Paper: arxiv.org/abs/2610.12599
Code: github.com/Infini-AI-Lab/STAโฆ
Website: infini-ai-lab.github.io/STAPโฆ
Beidi Chen retweeted
Today, weโre excited to launch the Datology Curation Studio, customizable frontier data curation for every team training its own models.
Data quality is the ultimate compute multiplier, and Curation Studio makes it easy for everyone.
Beidi Chen retweeted
Splash 1.3.0 is out! At launch we focused on decode speed. This time we worked on the wait before the first token.
Watch the part where we come back to a project. With SSD offloading on, the first token takes about a second instead of 19.
๐คฉ
Weโre open-sourcing lithos-metal ๐
Megakernels + DSpark speculative decoding run Qwen3.8-27B at 200+ tokens/s/user peak on one @Apple M5 Max.
Ultra-fast inference on your laptop. Try it with any coding agent in one command.
Code: github.com/lithos-ai/lithos-โฆ
Tech blog: lithosai.com/blog/lithos-metโฆ
The next frontier would be agents that get smarter as you use them. ๐ Our new ServeLearnBench puts continual self-improvement to the testโand reveals whatโs holding it back.
How well can agents continually self-improve from serving experience? Weโre excited to introduce our new benchmark, ๐๐๐ซ๐ฏ๐๐๐๐๐ซ๐ง๐๐๐ง๐๐ก:
Real-world deployment is not a one-time test of capability. The knowledge agents need is often hidden and can change over time.
ServeLearnBench tests whether agents can infer, apply, and revise this knowledge from interaction.
Across 5 learning harnesses ร 6 models, we find:
1. ๐๐๐ซ๐ ๐ ๐ฅ๐๐๐ซ๐ง๐ข๐ง๐ ๐ ๐๐ฉ๐ฌ ๐ซ๐๐ฆ๐๐ข๐ง. Agents can solve tasks when the hidden policy is given, but struggle to discover it from experience.
2. ๐๐จ ๐๐ซ๐๐ ๐ฅ๐ฎ๐ง๐๐ก ๐๐จ๐ซ ๐๐๐๐ฉ๐ญ๐๐ญ๐ข๐จ๐ง. Continual learning can be costlyโand can even degrade already-correct behavior.
3. ๐๐ฑ๐ฉ๐ฅ๐จ๐ซ๐๐ญ๐ข๐จ๐ง ๐ข๐ฌ ๐ ๐ค๐๐ฒ ๐๐จ๐ญ๐ญ๐ฅ๐๐ง๐๐๐ค. Better exploration strongly correlates with better adaptation.
Beidi Chen retweeted
Kernel agents can already beat hand-tuned kernels. Spinning up more agents is easy, but scaling GPU evaluation is still hard and expensive.
What happens when the agents scale faster than the GPUs?
Meet KCoral ๐ชธ: a lightweight shared GPU benchmark environment for agentic kernel development.
๐งโ๐ป Agents keep writing and revising code in their own workspace.
โก Evaluation is sent to KCoral, which schedules a shared GPU pool and returns correctness and timing.
๐ Scale across multiple GPUs and nodes through a unified API endpoint.
๐ Per-request isolation with only milliseconds of execution overhead.
By overlapping CPU compilation with GPU work across requests, KCoral further speeds up kernel evaluation. On a single NVIDIA B200, this translates to 2.58ร the throughput of sequential local execution.
๐คengram is finally in
Wow!
DFlash 2 is here! Qwen3.8-27B at 70 tok/s on an M5 Max MacBook Pro.
โก Up to 4.6ร the speed of autoregressive decoding, with the same output.
This is the next generation of DFlash, seeded at Z Lab and upgraded at Inco AI. Get one more accepted token on every pass, for free!
inco.ai/blog/dflash2/
๐ขAI is taking over the infrastructure it runs onโand already doing better. FlashRT achieves up to 70ร lower latency and 3.6ร higher throughput across five real-time apps, even delivering stronger results on less human-optimized AMD GPUs than on NVIDIA.
We used to handcraft static systems, but human expertise doesnโt scale. In the agent era, every application should have an end-to-end system customized by AI for its workload and hardware.
FlashRT is an early step toward that future.
AI is now building the infrastructure it runs on.
Getting real-time multimodal applications โ including live avatars, voice agents, video world models โ to actually run in real time takes serious manual systems work. Turns out a coding agent can do all the engineering work for you: up to 70ร lower latency and 3.6ร higher throughput, across 5 real-time apps.
Today we release FlashRT โก, an agent harness for real-time systems implementations and optimization. The developer writes only a simple reference spec, and the agent handles the rest end-to-end, producing efficient deployments across a range of GPU budgets in one shot, with no human intervention.
โ
Validated on 5 real-time applications that combine interactive video generation, text-to-speech, LLMs, etc.
โ
Runs on both NVIDIA and AMD GPUs; the agent optimizes for the hardware youโre on
โ
Can easily compose with third-party serving engines, the agent automatically implements orchestration
๐ Paper: arxiv.org/abs/2607.18171
๐ Website: infini-ai-lab.github.io/flasโฆ
๐ GitHub: github.com/Infini-AI-Lab/Flaโฆ
๐งต1/5
Beidi Chen retweeted
Today we're also opening the weights for Muse Glimmer, a great 30B parameter dense model that can run locally. Soon we'll also release the weights for Muse Spark 1.2, our latest foundation model. Meta is a strong supporter of open source and I'm proud of these releases. Congrats to @alexandr_wang and the MSL team for all your great work on these models.
Beidi Chen retweeted
First keynote talk of the day for AdaptFM @ #ICML2026 from @BeidiChen on "When AI Starts Building AI".
adaptfm.gitlab.io/talks/whenโฆ
lol Iโve been assuming Claude > GPT on basically everything. Turns out reasoning โ strategy.
๐๐ซ๐ ๐ ๐จ๐จ๐ ๐ซ๐๐๐ฌ๐จ๐ง๐๐ซ๐ฌ ๐๐ฅ๐ฐ๐๐ฒ๐ฌ ๐ ๐จ๐จ๐ ๐ฌ๐ญ๐ซ๐๐ญ๐๐ ๐ข๐ฌ๐ญ๐ฌ?
Our new project, AI Battle Arena, suggests the answer is no:
Claude models are strong at many reasoning-heavy tasks, like coding. But in hidden-information poker, Claude models stayed honest and paid an honesty tax. GPT-5.5 did much better because it was ๐ฐ๐ข๐ฅ๐ฅ๐ข๐ง๐ ๐ญ๐จ ๐๐๐๐๐ข๐ฏ๐ ๐ข๐ญ๐ฌ ๐จ๐ฉ๐ฉ๐จ๐ง๐๐ง๐ญ๐ฌ.
AI Battle Arena ๐ฒ is an open-source arena for evaluating frontier LLMs in strategic interaction, from poker to Gomoku to Colonel Blotto.
๐๐ฅ๐จ๐ : aibattlearena.com/blog.html
๐๐๐๐๐๐ซ๐๐จ๐๐ซ๐: aibattlearena.com/leaderboarโฆ
Rollout generation is becoming a central bottleneck in long-context RL says everyone โ and recent efforts from Cursor @cursor_ai and Fireworks @FireworksAI_HQ
show how just important disaggregating rollout and training is today.
Excited to share Sparrow๐ค, which makes sparse rollout practical and accelerate stable long-context RL.
Check it out!
RL is painfully slow ๐ญ โ bottlenecked by super-long CoT rollout.
๐ญ Sparse attention should help, but naive sparse rollout hits a brutal efficiencyโstability tradeoff:
A tedious trial-and-error sparsity sweep for each dense policy is required before an actual RL run.
๐คSparrow chirps no more pain! Introduce Sparrow: Sparse Rollout for stable and efficient long-context RL.
Sparrow finds that:
๐กAs long as we keep the tail distribution mismatch throughout the sparse rollout above a critical threshold, the RL training will be stable.
๐กEven cooler! Through comprehensive control studies of Qwen3-1.7B, 4B, 8B thinking models RL with 40K rollout max length, the critical threshold stays constant across model sizes.
๐กSparrow then finds the optimal dynamic sparse schedule to reach the threshold with minimal cost.
๐กSparrow's findings are empirically validated to generalize in Qwen3-14B, and hold on both Math and Coding RL.
๐คSparrow empirically helps achieve 2.2ร / 2.4ร / 2.0ร rollout speedup on Qwen3 1.7B / 4B / 8B thinking models, while keeping training stability over extended RL steps.
We release the ๐คbird in the following formats.
[1/n]
Paper: arxiv.org/abs/2606.08446
Code: github.com/Infini-AI-Lab/Spaโฆ
Blog: infini-ai-lab.github.io/sparโฆ
๐ค Inference-time sparse attention for RL is finally working.
Turns out the real challenge wasnโt sparsityโit was getting asymmetric off-policy rollouts to stay stable.
Sparrow discovers a robust stability threshold that lets us push sparsity to the limit: ~2ร faster rollouts, minimal tuning, and stable long-CoT RL.
RL is painfully slow ๐ญ โ bottlenecked by super-long CoT rollout.
๐ญ Sparse attention should help, but naive sparse rollout hits a brutal efficiencyโstability tradeoff:
A tedious trial-and-error sparsity sweep for each dense policy is required before an actual RL run.
๐คSparrow chirps no more pain! Introduce Sparrow: Sparse Rollout for stable and efficient long-context RL.
Sparrow finds that:
๐กAs long as we keep the tail distribution mismatch throughout the sparse rollout above a critical threshold, the RL training will be stable.
๐กEven cooler! Through comprehensive control studies of Qwen3-1.7B, 4B, 8B thinking models RL with 40K rollout max length, the critical threshold stays constant across model sizes.
๐กSparrow then finds the optimal dynamic sparse schedule to reach the threshold with minimal cost.
๐กSparrow's findings are empirically validated to generalize in Qwen3-14B, and hold on both Math and Coding RL.
๐คSparrow empirically helps achieve 2.2ร / 2.4ร / 2.0ร rollout speedup on Qwen3 1.7B / 4B / 8B thinking models, while keeping training stability over extended RL steps.
We release the ๐คbird in the following formats.
[1/n]
Paper: arxiv.org/abs/2606.08446
Code: github.com/Infini-AI-Lab/Spaโฆ
Blog: infini-ai-lab.github.io/sparโฆ
Beidi Chen retweeted
Vortex builds a layer for the current AI agents to make themselves more efficient, if you view AI agents as a species. We are soon to see AI agents directly program on an FPGA, defining efficient and expressive architecture, writing efficient low-level implementations, and training themselves. And, I do not know what can stop this. At that moment, whether AI can conduct research on something novel (rather than simply replicate what humans can already do) will determine whether 2025-2026 is a real genesis moment.
๐ Introducing Vortex โ sparse attention designed by AI agents, efficient at scale.
๐ Same accuracy, way more throughput โ across every model we tried ๐
๐น GLM-4.7-Flash (MLA) โ 4.7ร faster
๐น MiniMax-M2.7 (229B) โ 1.37ร faster
๐น Qwen3-1.7B (agent-discovered!) โ 3.46ร faster
๐ค How? An agent writes a flow in a few lines of Python; Vortex compiles it into fused kernels in a real serving stack (SGLang) and benchmarks it end-to-end.
๐๏ธ The design: a Python frontend (vFlow) over a page-centric tensor abstraction (vTensor) + a serving-integrated backend.
๐ arxiv.org/abs/2606.06453
๐ป github.com/Infini-AI-Lab/vorโฆ
๐ infini-ai-lab.github.io/vortโฆ
๐ infini-ai-lab.github.io/vortโฆ
Come and check out AstraFlow's new release~ While recursive agents are becoming one of the most exciting directions in agentic AI, we include this RL recipe in AstraFlow v0.1.1 showing how powerful dynamic sub-agent workflows can be in real-world coding tasks.
๐ AstraFlow v0.1.1 is out!
New in this release:
โข Dynamic recursive agents RL recipe
โข Megatron training backend
Inspired by dynamic agent workflows like @claudeai, this release reproduces the recursive agent RL recipe, where models learn to automatically spawn sub-agents to solve subtasks. (The implementation is based on the awesome Recursive Agent Optimization paper by @apurvasgandhi, @gneubig, @aviral_kumar2: arxiv.org/abs/2605.06639)
With existing RaaS support via @sgl_project and training backends including FSDP and Megatron, AstraFlow is moving toward a more flexible stack for large-scale agentic RL.
โญ Repo: github.com/Infini-AI-Lab/astโฆ
๐ Dynamic agents recipe: infini-ai-lab.github.io/astrโฆ
๐ขVortex feels like an early glimpse of recursive self-improvement for ML systems: agents discovering better architectures, compiling them into real serving stacks, and shifting the bottleneck from "can it code?" to "can we still steer it?"
AI building AI just went from theory to benchmark chart.
๐ Introducing Vortex โ sparse attention designed by AI agents, efficient at scale.
๐ Same accuracy, way more throughput โ across every model we tried ๐
๐น GLM-4.7-Flash (MLA) โ 4.7ร faster
๐น MiniMax-M2.7 (229B) โ 1.37ร faster
๐น Qwen3-1.7B (agent-discovered!) โ 3.46ร faster
๐ค How? An agent writes a flow in a few lines of Python; Vortex compiles it into fused kernels in a real serving stack (SGLang) and benchmarks it end-to-end.
๐๏ธ The design: a Python frontend (vFlow) over a page-centric tensor abstraction (vTensor) + a serving-integrated backend.
๐ arxiv.org/abs/2606.06453
๐ป github.com/Infini-AI-Lab/vorโฆ
๐ infini-ai-lab.github.io/vortโฆ
๐ infini-ai-lab.github.io/vortโฆ
Beidi Chen retweeted
Happy to see more RL systems moving toward this deployment shape.
This has been one of the core ideas behind AstraFlow since our early design: large-scale agentic RL should move beyond trainer-centered โengine modeโ and toward independently managed rollout/inference and training systems, connected by a clean rollout + weight-sync contract.
In AstraFlow (github.com/Infini-AI-Lab/astโฆ), we have been building toward this direction through rollout/trainer service decoupling, bring-your-own rollout service, flexible dataflow, and support for heterogeneous rollout backends.
Excited to see the broader community converging on this architecture. I believe this is where large-scale agentic RL infrastructure is heading.
Most RL frameworks are moving from โengine modeโ to โserver modeโ.
slime goes one step further: the RL job does not need to own the rollout servers at all.
Bring your own SGLang fleet, already deployed and managed by your serving system. slime connects to it, registers it with the router, generates rollouts, and syncs updated actor weights via NCCL or disk-based full/delta transport.
This is the deployment shape we believe large-scale agentic RL is moving toward: training and inference as independently managed systems, connected by a clean rollout + weight-sync contract.























